Here are your parts
Replacement parts for WHIRLPOOL KDRP407HSS4 RANGE-DUAL FUEL | AppliancePartsPros.com

Here is a service manual which should help with dismantling.
http://appliancedigest.c...tion-oven-service-manual
You have to join the site to download the manual but it is free and this is a very good site for manuals and other info for the appliance repair DIYer.

Looks like the display is a separate device so you may want to try the following before replacing any parts.
Connector Cleaning / Checking
Unplug the unit
Open it up
Remove the ribbon cable from the keypad to the control board at the control board.
Clean the edge connector.
If it is the type where there is not a connector just the insulation is removed, it can be cleaned with a pencil eraser. Do not use an ink eraser as it is too abrasive.
Check the wires and solder connections.
Check the tracks in the ribbon cable for hairline cracks. A magnifying glass helps here.
Would not hurt to clean the connector on the board. Use electronics contact cleaner or isopropyl alcohol and a tooth brush. Be gentle and do not reconnect till all the solvent evaporates.
Reconnect everything and give it a try.